On Saturday night, Iran and the P5+1 powers — the U.S., Britain, France, Russia, and China, plus Germany — reached a six-month deal to halt Iran's nuclear program in return for sanction relief worth an estimated $7 billion. On Sunday, the negotiating powers started the process of selling the deal to their various constituencies.

For Iranian President Hassan Rouhani, support for the interim deal was broad-based and spanned the political spectrum, from those advocating increased engagement with the global community to some hard-liners primarily concerned about relief from the sanctions crippling Iran's economy. Ayatollah Ali Khamenei gave his stamp of approval, saying "the nuclear negotiating team deserves to be appreciated and thanked for its achievement," which "can be the basis of the next wise measures."

For Obama, the reception was decidedly more mixed. There were the predictable partisan divisions on the Sunday talk shows, with Republicans criticizing the deal as inadequate and Democrats calling it a diplomatic breakthrough or, at least, a promising first step. But some of Obama's allies on Capitol Hill were skeptical. Sen. Chuck Schumer (D-N.Y.), for example, said he was "disappointed" with the deal "because it does not seem proportional." (The agreement doesn't need congressional approval.)

Here are the basic elements of the six-month agreement. (For more details, the White House has a fact sheet.) In return for easing a limited number of sanctions — primarily by unfreezing some Iranian bank accounts — and a six-month commitment to not imposing new ones, Iran has agreed to freeze or slightly roll back just about every aspect of its nuclear program. That includes:

No net increase in its stockpile of enriched uranium

No new production of uranium enriched past 5 percent

Destruction or dilution of all uranium enriched to near 20 percent — close to weapons-grade

Install no new centrifuges, leave idle more than half the centrifuges it has already installed

"Two weeks to two months may seem like barely any kind of gain," says Rob Wile at Business Insider. But combined with the more intrusive inspections, "the world will now be more aware of, and be able to respond more quickly to, any attempt" by Iran to build a nuclear bomb. Is that worth easing sanctions? Here are the pros and cons of the deal:

1. DEAL OPPONENTS

What's wrong with the deal?Critics contend that the agreement doesn't go far enough to make it worth halting the sanctions regime. If Iran wants a reprieve, it should halt all uranium enrichment and make clear that Iran has no right to enrich uranium, tell the world what nuclear activities it is conducting at Parchin military base, freeze all centrifuge production, and start dismantling it nuclear facilities, says Danielle Pletka at the American Enterprise Institute's AEIdeas.

And what Iran gets for merely pushing the pause button is "the beginning of the end of international cooperation on sanctions," says Pletka. "The reversal in momentum for sanctions and the loss of the psychology of impenetrable sanctions is of immeasurable value to Tehran."

Yes, "this interim agreement is badly skewed from America's perspective," says John Bolton at The Weekly Standard. Allowing Iran to continue enriching uranium, especially, amounts to "abject surrender by the United States." Along with buying time and sapping the sanctions of potency, the deal is rotten because "Iran has gained legitimacy," Bolton adds. "This central banker of international terrorism and flagrant nuclear proliferator is once again part of the international club."

The lead dissenting voice isn't a pundit or member of the U.S. Congress, though; it's Israeli Prime Minister Benjamin Netanyahu. "What was reached last night in Geneva is not a historic agreement, it is a historic mistake," he said as soon as the news broke. "Today the world became a much more dangerous place because the most dangerous regime in the world made a significant step in obtaining the most dangerous weapons in the world."

What comes next?Just like a similar, phased nukes deal with North Korea, this agreement will lead nowhere, says AEI's Pletka. Six months will pass, and Iran will continue its drive for a nuclear missile. "There will be no phase two."

With the U.S. and Europe committed to appeasement, says Bolton at The Weekly Standard, "in truth, an Israeli military strike is the only way to avoid Tehran's otherwise inevitable march to nuclear weapons, and the proliferation that will surely follow."

2. DEAL SUPPORTERS

What's good about the deal?The six-month deal "does not achieve permanent and total dismantlement of Iran's nuclear program," but "no one can seriously argue that it doesn't make the world safer," says The New York Times in an editorial. Obama and Rouhani deserve credit for "resisting fierce domestic opposition and a 30-year history of animosity between the two countries" to take this "important step toward resolving the increasingly dangerous dispute over Iran's progress on production of a nuclear weapon."

The Iranian deal is nothing less than a "triumph," and it "goes way beyond what anybody could reasonably have hoped for" even a few weeks ago, says Fred Kaplan at Slate. It should build trust between the U.S. and Iran, giving negotiators time to do the much harder work of reading a comprehensive agreement. If they fail, Iran will get hit by tougher sanctions and the U.S. can say it gave diplomacy a real shot. "Had George W. Bush negotiated this deal, Republicans would be hailing his diplomatic prowess, and rightly so."

Yeah, let's be real, says Martin Longman at Washington Monthly.

Any agreement with Iran was going to have to allow the Iranian government to argue that they'd gotten a good deal. Likewise, any agreement was going to be opposed by Israel and Saudi Arabia, and Saudi Arabia's satellites in the Gulf region. Any agreement with Iran was also destined to be opposed by President John McCain, Vice-President Sarah Palin, and Secretary of State Lindsey Graham. All of that was baked in the cake, and none of it has even a little bit to do with the details of the agreement. [Washington Monthly]

The hard work is ahead, but after a decade of no diplomatic progress and steady Iranian nuclear advancement, Rouhani's election gave us all a window to reach a breakthrough, says Amy Davidson at The New Yorker. "It would be self-destructive on America's part not to seize this moment." And Secretary of State John Kerry "is certainly trying."

What comes next?The interim agreement, to paraphrase John Lennon, gives peace a chance. Kerry "appears to have gotten his fingers on the edge of something that could be historic," says The New Yorker's Davidson. "Now the task is to not let go."

The comprehensive agreement "will be a much harder nut" than this interim pact, says Slate's Kaplan. It would require Iran to give up its nuclear ambitions, and the West to phase out its sanctions, and there's no guarantee that either of those are possible. This first step is important," Kaplan adds. And "in a year's time, it may be seen as a small step and a brief, naïve step at that. But for now it's a step rife with historic possibilities; it's a step that should be taken with caution but also with hope and gusto."